Just an interesting tidbit - I went to the largest resale house in Canada and tried to sell them a lab diamond - they would not even accept it. Said it has 0 resale value (yes, zero). I was en route to purchasing a tennis bracelet from Vrai (lab diamonds) and so glad this experience happened prior to that purchase, as the bracelet was not cheap by any means. The guy at the resale house told me to avoid lab diamonds as there's practically 0 market for it... so essentially you pay a bunch (if it was cheaper there would be a worthwhile argument) and it actually has no intrinsic or holding value.
Since then I decided to shelve the idea of lab diamonds unless I had extra cash to burn (literally).